Don’t get too excited about “DiddyUp.” Kate Upton and Diddy have shot down a laughable front-page report they’re “hot and heavy.” Of the pair hooking up at a Miami club and New York restaurant last month, Upton’s rep said, “She has never been to either of those places, was not in Miami nor in New York with Diddy. She was on vacation with her family. She and Diddy don’t know each other at all. They met in passing a year ago. It is completely false.” “Not at all true,” Upton tweeted yesterday. Diddy added, “Attention all Media. I don’t even know Kate Upton personally! I’m not dating her! What’s being reported is not true. END of story!” A friend of Upton’s added, “She is single at the moment.”